This invention relates generally to electrical machines, and more specifically to methods and systems for controlling temperature in an electrical generator.
At least some known electrical generator systems are designed to operate within specific environmental conditions. For example at least some known wind turbine generators, are designed for sea level application with a site altitude less than approximately 1000 meters. However, such wind turbine may be installed in a location where the specific environmental conditions that are used to define the design requirements are exceeded. If the wind turbine generator is installed in a location having an altitude and/or ambient temperature that is outside the specific environmental conditions in the design criteria, the cooling capability of the wind turbine generator may be reduced and the generator may experience an over temperature condition during operation. In such a location, to maintain stable power operation of the generator without de-rating the wind turbine generator, the cooling of the generator would have to be improved.
One known solution is the implementation of an enhanced cooler, for example, a cooler having axial and/or radial cooling fans may be adopted to replace an original cooler. However, the new design of enhanced cooler and/or the design of the generator, as well as increasing the amount of electrical equipment associated with the wind turbine generator is costly. Additionally, retrofitting new equipment on an installed wind turbine generator at high heights of sixty-five meters or more is more costly.